A study in PS1-M146V knock-in FAD mice showed that decreased calcineurin activity is a common phenomenon in aging-related memory decline and may account for memory defects in AD, together with mutations in the gene encoding for GSK-3β substrate presenilin 1 (PS1) [152], which are critical for amyloid-β (Aβ) generation. Here, GSK3B is linked to Alzheimer disease.